Add shell script copyrights

src/php/bin/interop_client.sh

src/php/bin/run_gen_code_test.sh

src/php/bin/run_tests.sh

tools/buildgen/generate_projects.sh

tools/distrib/check_copyright.py

tools/gce_setup/builder.sh

tools/gce_setup/cloud_prod_runner.sh

tools/gce_setup/compute_extras.sh

tools/gce_setup/grpc_docker.sh

tools/gce_setup/interop_test_runner.sh

tools/gce_setup/new_grpc_docker_builder.sh

tools/gce_setup/new_grpc_docker_builder_on_startup.sh

tools/gce_setup/shared_startup_funcs.sh

tools/run_tests/build_node.sh

tools/run_tests/build_php.sh

tools/run_tests/build_python.sh

tools/run_tests/run_lcov.sh

tools/run_tests/run_node.sh

tools/run_tests/run_python.sh